EP1106309A2 - Robot control method and device - Google Patents

Abstract

The robot control method is based on sensor data from sensors with specific sensor data structures that are processed into robot control data in a control data structure that can be used by a control program. The sensor data are converted into control data of a uniform data structure and/or the internal data of the robot control program are converted into control data of a uniform data structure. Independent claims are also included for the following: an arrangement for controlling a robot.

Description

The invention relates to a method and a device to control a robot based on sensor data of sensors with their own sensor data structures.

So far it has only been possible with considerable effort, different Sensors and sensor groups in a robot control. Use different sensors although, like the robot controller, largely standardized Hardware interfaces, but they assign theirs own, especially different, data structures on. Accordingly, the robot controller must be different Data formats, structures, transmission protocols and transmission speeds of the respective sensor Known robot controls are also available mostly only over fest. implemented a n access options for sensor data on the Robot Pro grams. Adaptation to new sensors and creation new work mechanisms can only be carried out by the manufacturer become what is usually a modification System software requires such changes Intervene deeply in 1 the system programs are extensive. Test required 1 to ensure security Adjustments at user level with the help of existing ones Communication interfaces are usually not sufficient the speed requirements of the to be influenced Process. When connecting complex sensors therefore often the detour via additional external and expensive computer hardware chosen.

For example, Completely implemented software interfaces for visual sensors or tracking sensors. However, such implementations are mostly based on specific sensor types and brands tailored and thus neither with regard to the protocol nor with regard to flexible processing of data.

Proceeding from this, the invention is based on the object a method and an apparatus for controlling a To create robot in such a way that without intervention in the actual control program of the robot an adjustment different sensors and thus in a simple way the use of different sensors is possible.

According to the invention, this object is achieved by a Method for controlling a robot of the aforementioned Kind of solved with the sensor data in robot control data one that can be used by a control program Tax data structure are processed. A generic The device is designed to achieve the object that a processing device for processing the sensor data in robot control data one of one Control program usable control data structure is provided.

To achieve the possibility of flexible cooperation a robot controller equipped with its own standard hardware interfaces, with different Sensors that use standard hardware interfaces feature, but specific data in specific To deliver formats, the invention therefore provides that robot control by introducing a user-configurable Sensor data processing layer in the Able to process specific sensor data in such a way in particular to standardize and convert, that the control program runs through this layer can be easily processed. Sensor data can in particular in any way combined and then the system program to trigger Actions are fed.

Due to the invention between the sensors and the Control program of the robot provided separate processing layer to provide the control program processable, adapted to this tax data Use of various sensors with a robot enables the same control or system program without that this must be changed as such; during use different sensors is not an intervention in that Control program necessary. The processing of the sensor data can be modular, so that a light Configuration to adapt to different sensors is possible by the user. In particular can the processing of the sensor data by the user through the agreement, linking and parameterization predefined function blocks can be configured. The The function blocks are linked and parameterized in particular so that the resulting structure the safety functions of the system program are not impaired. The structures can continue in this way during the runtime of a robot application event-controlled switching can be changed. For this the invention preferably provides that the Sensor data in control data with a uniform data structure be converted that the control data by appropriate Processing operations on actuator data processed and that the actuator data is checked, if necessary be limited and sent as robot control data to the Control program of the robot are passed. There for Controlling a robot not just external sensor data but also internal data of the Robot control itself, the invention suggests in one preferred embodiment further before that internal data the robot controller in control data with a uniform Data structure to be converted using control data structure identical to that of the external sensor data is; the internal data is thus used as data from pseudo sensors shown.

Different sensors can be used in the robot controller can be integrated in a simple manner without a Intervention in the actual control program required i which minimizes security risks and changes associated test effort is reduced. The invention enables existing interfaces of sensors and Program.

Basically during the processing cycle (reading cycle) can be determined by external events one or more internal clock generators (timers) are provided be, with sensor, control, Actuator and / or robot control data an averaging and / or filtering is carried out. If a later one Processing is done at a lower clock rate a preferred embodiment before that when editing the sensor, control, actuator and / or robot control data averaging and / or filtering performed becomes. This makes effective interference suppression achieved.

In a further embodiment, it can in particular be provided be that sensor data from several sensors is processed in parallel and / or that several processing paths for parallel processing of sensor data from a sensor provided using different evaluation strategies are, in particular those according to a certain Evaluation strategy obtained data depending on certain Events for use by the control program be handed over to this.

Operation of a sensor with several evaluation strategies is particularly useful if the evaluation strategies differ so much that the necessary ones differ Switching no longer in a signal processing path let it be realized. In this case, two or several independent strategies in separate Programmed signal processing paths. Another important use case for selectable strategies is error handling, the different approaches such as. Sensor initialization, program stop, call new programs or suppression of actions. To select a strategy, the associated signal processing path activated and the not used deactivated. To activate the specified events are used:

Program sequence, such as start / stop, change of operating mode or Program command. Variable, like the value of system variables or user variables. Interface data like that State of binary I / Os, analog I / Os, serial Interfaces or parallel interfaces.

Within the scope of the invention, for example, a Controller device based on the control data received a control process depending on a condition carried out.

The invention makes it possible to use sensors for a wide variety of applications Use problems, e.g. Force-moment sensors, the contacts of the robotic arm on unwanted Positions and / or with impermissibly high forces detect, so sensors that are based on the measurement of the Weight of the grapple to determine if any of this seized object after opening and returning it on Gripper gets stuck. Sensors can still be used that are sorting workpieces by allow their weight, this by default of Thresholds happen. Other sensors that can be used use a combined displacement and force measurement to determine whether a connector and a counterpart actually correct and completely plugged together by the robot. Sensors for monitoring stress tests, used, for example, to check glued areas be the strength and way of exceeding Monitor predefined threshold values. In the same way sensors can be used, for example when pulling cables monitor the traction where a Exceeding them to damage or complete Destruction of the cable would result. While at in this case force monitoring in the direction of pull is required is transverse to the direction of movement in the case of metal-cutting manufacturing processes, in order to to guarantee constant cutting forces. Other areas of application of sensors on a robot are tracking a given contour, like a groove.

Fig. 1

die Einbindung einer die Erfindung umsetzenden Sensorprogramms in die gesamte Robotersteuerungsoftware;

Fig. 2

eine schematische Darstellung einer erfindungsgemäßen Steuerung des Ablaufs der eines Roboters;

Fig. 3

ein Verarbeitungspfad für Sensordaten eines Sensors;

Fig. 4

eine vergrößerte schematische Darstellung der Reglereinrichtung mit ihren Angabefunktionen;

Fig. 5

eine schematische Darstellung eines Datenverarbeitungsvorgangs in einer Reglereinrichtung.

Fig. 6a-6g

Bildschirmausdrucke zur Programmierung eines virtuellen Sensors über Inline-Formulare durch einen Benutzer;

Fig. 7

den Quellcode des gemäß der Abfolge der Figuren 6a bis 6j oder aber direkt durch einen Experten erstellten einfachen Sensorprogramms; und

Fig. 8

die durch das Programm angelegte Struktur im Systemprogramm.

Further advantages and features of the invention result from the following description, in which an embodiment of the invention is explained in detail with reference to the drawing. It shows:

Fig. 1

the integration of a sensor program implementing the invention into the entire robot control software;

Fig. 2

a schematic representation of an inventive control of the sequence of a robot;

Fig. 3

a processing path for sensor data of a sensor;

Fig. 4

an enlarged schematic representation of the controller device with its specification functions;

Fig. 5

a schematic representation of a data processing operation in a controller device.

6a-6g

Screen prints for programming a virtual sensor via inline forms by a user;

Fig. 7

the source code of the simple sensor program created according to the sequence of FIGS. 6a to 6j or directly by an expert; and

Fig. 8

the structure created by the program in the system program.

The core of a robot controller 1 is a robot system or Control program 2 that controls the robot 3. The tax program 2 is from a user interface 4 User 5 operable. It receives input data from sensors 6 about driver 7. The invention now provides that between the sensor drivers 7 and the control program 2 its own sensor data processing layer in the form of a Sensor frame program 8 is provided, on the one hand via the user application program that the movements controls the robot and on the other hand via a Unit 11 for event-driven strategy selection based on can be influenced by occurring states and signals. User application programs, event-driven strategy selections 11 and sensor programs in the sensor framework program 8 can be programmed by the user 5.

The workflow of the control according to the invention for a robot is shown in FIG. 2.

The control 1 according to the invention, as said, first sensors 2 of different types, the data output their own different data structure. The If necessary, sensor data can initially be standardized become. Sensors providing the data can also Pseudo sensors 2 'belong that are not real measured Pass sensor data, but system data of the robot controller themselves, which correspond to the format of sensor data and the anlog to the sensor data for further Can be used in the controller.

The sensors 2 are followed by the actual conversion devices 13, also referred to as "virtual sensors" because the robot control program from data transferred to the conversion devices when he sees appropriate sensor data, so only that Conversion device as virtual upstream - Sensor sees.

The conversion device provided according to the invention 3 reads in sensor data and error codes. The conversion facility 13 includes a conversion unit, such as a coordinate transformation unit. There are also different input sensor values linked, possibly to a result that only consists of a value that exists in an adjustment unit multiplied by a preselectable value or additive can be provided with an offset. The initial value then becomes the control program for further use to hand over. A test facility for checking the Error codes can be a defined action in the event of an error cause.

Filters 14 can be used for the conversion devices 13 downstream. The output data of the conversion devices 13 can in a first alternative via a threshold switch 15 as the Boolean value Control program are fed. The threshold switch 15 works with the data received from the converter to be delivered. Through the threshold switch 15 becomes a condition - greater than, less than - defined, which he continuously reviews, the comparison value of the condition can be changed, to be able to vary the sensitivity easily. On The threshold switch has only one input. The Output signal of the threshold switch determines whether from Control program a control process or an action is performed.

Output values can be used in an additional or alternative way of threshold switches through a link unit 16 can be linked together. Such complex switching conditions can be created. While the link unit 16 on the input side several switches or previous links is connected on the output side with a control process or links can also be provided. A link unit 16 can also with itself be connected. The linking unit contains in the As a rule, a fixed link that evaluates in cycles and the result of the following elements Is made available.

Furthermore, in the context of the control according to the invention Controller devices 17 may be provided; take this Data from one or more conversion devices 13 counter, from which a correction offset and / or Override for correcting a position (offset) or for multiplicative influencing of the travel speed of the robot (top ride) is determined. There can be several Regulator 17 may be provided. A controller 17 can Integrator 18 may be arranged downstream of the controller 17 received correction frames integrated. The initial values the controller 17 are in turn directly or indirectly via the integrator to perform control functions taken over by the control program. This defines the actual function performed by the robot is performed. This can range from stopping the robot enough to set an exit.

The sequence of the method according to the invention is based on of a processing path shown in FIG. 3. The Processing is controlled by a timer 21 or Timer that determines the times at which the data is transferred specifies a clock, what in Fig. 3 by the switch 22, 22 ', 22' 'is represented. The transfer of the data can also be triggered by external events.

Available from the sensor in the "Sensorlist" provided data are in a conversion facility 3, the "virtual sensor" unified. This has function blocks for this, which are created by user programming are network-like connectable. The functions operators such as basic calculation types, Squaring and rooting as well as Boolean operators, in addition filters, such as high, low, and bandpass filters, Averaging, and finally transformations for frame arithmetic and matrix multiplication included. The virtual sensor 3 provides the processed ones Sensor data as control data in a control list ready. This includes a data structure with "Type" to describe the origin of the sensor signal and Identification of the "Dimension" sensor type to indicate the Unit of the signal in SI units (e.g. Nm); "Dimfactor", by which the signal value is multiplied by the Obtain the signal value in the desired SI unit, "Value" as the actual sensor value, "Time" for definition the time of signal generation in the sensor (Timestamp) and "Enabled" to determine whether the associated Value is further processed or not. Insofar as control internal data is used for processing analogue to the sensor data as data represented by pseudo sensors.

The control data of the controller are also clocked processed, the clock of the switch 22 'of the of switch 22 (and that of switch 22 '') differ can and taken over by the controller 17. This can create function blocks for realizing Boolean Operations (AND, OR, XOR, NOT), control functions, such as 2-point and 3-point controllers, P controllers, integrators, PID controller, further comparison and switching functions such as comparators with or without hysteresis and others Delay, limit, integration, Differentiation and non-linear characteristics.

The control device 17 in its sequence of signal processing with an example of the function blocks shown in Fig. 4. The actual control process is a target-actual comparison preceded.

A specific form of processing in the Control device is shown in Fig. 5.

The values or data of the control device 17 are as Result values in an actuator list of an actuator unit 23 provided that in the actuator list Result values provided by the controller device 17 reads the data of a review at specified times the value range in the sense of a plausibility check and, if necessary, a conversion and if necessary, subject to limitation and finally to the robot's own control or system program 2 in Form of a robot list for effecting control actions of the robot passes. These control actions can include: a sequence control of the robot with start or stop, branches in the program flow and the Selection and start of certain program components, motion controls such as positive offset, force injection or Override, and finally general data management to update variables.

As was already apparent from FIG. 2, a parallel one Operation of data from multiple sensors, these can be configured identically or differently, be performed. In addition, as by the Branches of Fig. 2 can also be seen, the Evaluation of the data of a sensor in several evaluation strategies take place, depending on the events occurring the program sequence, the values of variables or Interface data, one or the other signal processing path activated and those not used deactivated become. Evaluation strategies can be combined, further error handling can be carried out.

Overall, this results in a process sequence according to the invention in which data from sensors 2 are first read out, possibly also the pseudo sensor 2 ' and then they are converted. The unified Data is then processed further by it is checked whether they exceed predetermined threshold values or fall below, linked to each other or subjected to a regulation process, wherein this by the user in a simple manner in each case in adaptation is programmable on the sensor or sensors provided, without interfering with the actual robot control program becomes. Because of the data that the control program from the robot list, if necessary suitable control operations for the robot causes.

With the invention, it is in the implementation of sensor-specific Program files are no longer necessary Function and safety test of the actual control software perform. Programming deficiencies, in sensor adaptation relevant parts of the program lead under Wrong behavior, but not security risks, because in the actual control or system program of the robot is not intervened and in remaining modules that have been fully tested in the manner described can be used with complete error handling can. The programming of the tasks in the sensor framework program and the strategy selection can be done both with operator prompting as well as in an expert mode. in the first case, a user without relevant IT and Programming knowledge the programming of the sensor data evaluation while contributing his knowledge of what is to be carried out Execute work process, being in this user mode forms for the integration of function modules can use and to enter the required Requested parameters in given input fields is being monitored, the range of values being monitored at the same time and a plausibility check is carried out. The integrity of the security functions of the tax or System software of the robot is retained in any case.

Figures 6 to 8 relate to a virtual sensor for a simple application, namely tracking a Edge whose position and direction is known with automatic Stop at an unexpected obstacle. To do this a force sensor can be created, the three forces in one measures the cathesic coordinate system. One has Transformation of the forces into a force in the direction of movement of the robot using a virtual sensor. When the real sensor hits an edge it must be stopped and another Approximate edge direction. For persecution the edge is a transformation of the forces in a force across the direction of movement of the robot make a virtual sensor, taking the shear force for tracking the robot on the edge by a Control algorithm is used.

6a is initially an empty program body shown. The user first chooses which one to use Technology using the "Technolog" button the top edge of the screen, whereupon a Range of functions offered under this technology become. From this, he selects a new sensor, which he KraftY gives names (Fig. 6b). In Fig. 6c that is Putting on a sensor is shown, which is an accompanying Record the force in the Y direction of the connected DLRFT sensors included. The following is shown how a reaction condition with the frame "Stop on force" is created. If the recorded Force value in the Y direction exceeds 30% of the maximum value, the robot stops immediately. From Fig. 6d can be seen that the user within the framework of the inline forms a number of ways by clicking the in offered for processing the inline mask will be the percentage when the Maximum value a function is exercised and the type of Function, whereby the normal stopping (Stop Normal) is selected. 6e shows the input of a normal movement, with the previously generated monitoring is already active during this movement. In the further (Fig. 6f) can be monitored by the command "DEL Condition: Stop on force "can be deactivated, whereby the Inline form, via which the deactivation is selected is itself not shown. With the in Fig. 6d shown command "Delete Sensor: KraftY" is the Sensor deleted when it is no longer needed.

7 shows one in this way or by direct input of an expert the entered source code with the specification of the functions in the individual lines of the Source code program.

8 shows the structure created by the program in the system program.

Reference list

1

control according to the invention

2nd

Control program

2nd

Pseudo sensors

3rd

robot

4th

user interface

5

user

6

Sensors

7

driver

8th

Sensor frame program

1 1

Strategy selection

12th

Linking unit

13

Conversion facility

14

filter

15

Threshold switch

16

Linking unit

17th

Regulator device

18th

Integrator

22

switch

22 '

switch

22 ''

switch

23

Actuator unit

Claims (25)

Method for controlling a robot based on Sensor data from sensors with their own sensor data structures, characterized in that the Sensor data in robot control data one by one Control program usable control data structure are processed. A method according to claim 1, characterized in that the sensor data is more uniform in control data Data structure to be converted. A method according to claim 1 or 2, characterized in that that internal data of the robot controller in Control data with a uniform data structure be converted. A method according to claim 2 or 3, characterized in that that the control data by appropriate Processing operations on actuator data processed become. A method according to claim 4, characterized in that the actuator data is checked, if necessary be limited and sent as robot control data to the Control program of the robot are passed. Method according to one of the preceding claims, characterized in that sensor, control, Actuator and / or robot control data with different Clocks are processed. A method according to claim 6, characterized in that when processing the sensor, control, Actuator and / or robot control data an averaging and / or filtering is carried out. Method according to one of the preceding claims, characterized in that sensor data of several Sensors are processed in parallel. Method according to one of the preceding claims, characterized in that data from a sensor in parallel using different evaluation strategies be evaluated. A method according to claim 9, characterized in that according to a certain evaluation strategy data obtained depending on certain events passed to the control program for use become. Device for controlling a robot based on Sensor data from sensors with their own sensor data structures, characterized in that a Processing device for processing the sensor data in robot control data one from a control program usable tax data structure is provided. Device according to claim 1, characterized in that a device for converting the sensor data in control data of uniform data structure is provided. Device according to claim 11 or 12, characterized in that that facilities for conversion internal data of the robot controller in control data provided with a uniform data structure is. Device according to claim 12 or 13, characterized that a controller device for processing the control data through suitable processing operations is provided for actuator data. Device according to claim 14, characterized in that an actuator device for checking the Actuator data, possibly to limit them and for transfer as robot control data to the Control program of the robot is provided. Device according to one of claims 11 to 15, characterized in that clocks with each other independent output clocks for the individual processing devices are provided. Device according to one of claims 11 to 16, characterized by means for averaging and / or filtering the sensor, control, actuator and / or robot control data, especially during processing the same with different measures. Device according to one of claims 11 to 17, characterized in that several processing paths for parallel processing of sensor data several sensors are provided. Device according to one of claims 11 to 18, characterized in that several processing paths for parallel processing of sensor data of a sensor using different evaluation strategies are provided. Device according to one of claims 11 to 19, characterized by a switching device (9) for Activation or deactivation of processing paths depending on one or more Conditions. Device according to one of claims 11 to 20, characterized by hierarchical control modules. Device according to one of claims 11 to 21, characterized by a hierarchical and modular built user interface. Device according to claim 21 or 22, characterized through a level of modules to select Art of a virtual sensor. Device according to one of claims 21 to 23, characterized in that modules are provided, those to be monitored by a virtual sensor Actions include. Device according to one of claims 21 to 24, characterized by modules for defining the actions effecting parameter.

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